There are generally two ways in which commercial mail senders apply postage to their mail. The most common way is by use of a postage meter which is leased by the mailer from a postage meter manufacturer with which the amount of postage required is applied to each mail piece. Inserter systems have been developed whereby inserts may be placed into an envelope, the envelope may be sealed, addressed and have a postage indicia applied thereto. The mail pieces may be weighed on the fly or individual weighing may not be required if all the mail pieces are of like kind, i.e., only a sample mail piece need be weighed. These acts of processing mail, usually on a periodic basis, may be performed at a relatively high rate of speed.
A second method of mailing large quantities of mail pieces is the permit mail system. In such a system, the mail sender places a permit number on the mail pieces and prepares a manifest listing that shows the type and number of mail pieces being mailed on each occasion and the postage required.
With both systems, inspection at the site of the mail sender is required. In the case of the postage meter, the lessor of the postage meter, i.e., the postage meter manufacturer, is required by law to inspect the postage meter at least twice a year to ensure that there is no evidence of tampering with the postage meter that will indicate an attempt to obtain unauthorized postage. In the case of permit mail, large quantities of the same type of mail will be mailed at one time and the postal service will conduct an inspection to verify that the manifest listing accompanying the permit mail accurately accounts for the amount of postage due for the mail that has been processed by the postal service. This is accomplished through an inspection on the part of the postal service by examining the records of the mail user on every occasion.
Obviously, each of these two systems has certain drawbacks. In the case of on-site inspection of postage meters, with the large number of postage meters in use by large mail senders it is an expensive matter for the inspect thereof. Furthermore, postage meters that process large quantities of mail must be replaced relatively frequently because of wear. With regard to the permit mail system, the shortcoming lies in the need of the postal service to send a representative frequently to the various mail sender locations to ensure that the mail sender is accurately accounting for the quantity of mail being sent. Such a scheme is not totally reliable as it relies upon on-site verification using the mail senders records which are not secure.